【摘要】 以冬小麦品种 8901、5-98、99-92和 104等品种的幼穗和幼胚为材料,用基因枪转化含逆境诱导转录因子 DREB 和bar 基因的质粒 pBAC128F(7 024 bp)。经筛选与植株再生,共获得 70 多个转基因小麦植株及其后代株系。转基因株系经PCR 分析和 RNA 点杂交检测,结果表明外源转录因子 DREB 基因已稳定整合到转基因植株及其后代株系中,并且在部分后代株系中获得了表达。叶片脯氨酸含量测定表明,有 16 个转基因株系的脯氨酸含量与非转基因对照相比,增加相当显著,其中10个株系的脯氨酸含量在1 100 μg/g以上,比对照提高了2倍多。室内抗旱模拟实验表明,转基因株系停止浇水15 d 后,叶片仍然表现绿色,而对照叶片则失绿、枯干;复水 10 d 后,转基因株系恢复活力,对照则死亡。研究表明,利用逆境诱导型启动子(rd29B)来增强外源DREB基因的表达,能显著改良小麦的抗旱性。更多还原

【Abstract】 Expression vector pBAC128F, which carries DREB transcriptional factor gene driven by drought inducing promoter rd29B and bar gene driven by CaMV 35S promoter and maize Adh1 gene first intron, was transferred into the explants of immature inflorescence and immature embryos of hexaploid winter wheat cv. 8901, 5-98, 99-92 and 104 by particle bombardment. More than 70 resistant transgenic plants were obtained. Genomic PCR and RNA dot blotting analyses showed that DREB gene had been integrated into wheat genome of the transgenic plants (T0 and T1) and was well expressed in offspring seed of different transgenic lines. The content of proline in leaves and seeds of T2 transgenic lines was analyzed. Among 16 tested transgenic lines, 10 trans-genic lines exhibited more than two fold of proline level in leaves as compared with CK plants. Under drought condition, after stopping water for 15 days the leaves of transgenic lines were still green, while CK were faded. After rewatering for 10 days, the leaves of transgenic lines maintained their green, while all CK plants were dead. Our research suggested that introducing a novel DREB transcriptional factor into wheat is an effective way to improve its drought-tolerance ability.更多还原